I'm reverse engineering the PC boards in my Wang 2200. I have been able to find most of the chips that have been used on the board I'm currently workign on, except for a couple. Does anybody know the pinout for these? 1) 8T10, quad latch (with either tristate or open-collector outputs, I don't know which) It is a TTL device, made by Signetics, I think. 16 pins. 1976 date code. (N8T10B is the fullly qualified part name) 2) This one is a reverse job. The microcode board has quite a few mask ROM chips. I don't care what the actual part number is, but I'm hoping someone will say, "hey, that pinout is just like a ..." so that I can find a prom programmer to read the thing. If I have to, I guess I could build a parallel port dongle to read them. Here's what I know: 24 pins data out on pins 16-23 pin 1 is +5V pins 2-8, 10, 11, 13, 15 are the address pins pin 14 is either a chip select or output enable; active low pins 12 and 24 are pulled up to +5; chip selects maybe? pin 9 might be -15V (!) Embarrassingly, I can't find a connection to GND. unfortunately, I don't know the backplane connections either, so I can't identify if pin 9 is really -V or just an alternate ground (but I see a bypass cap between the digital ground and this net, so it makes me think). BTW, I have started a web page to archive this information if anybody cares: http://www.thebattles.net/wang/wangtech.html So far I only have one simple I/O board done. Once I have enough of the system figured out, I'll write an emulator for it. That's where all this reverse engineering drudgery becomes fun. Thanks for any suggestions. ----- Jim Battle == frustum(a)pacbell.net